Atomistic simulations of helium clustering in copper

Abstract

The formation and growth of helium (He) clusters in copper (Cu) bulk were studied using molecular dynamics simulations. During the growth of a single He cluster in a Cu box, stacking faults were found to occur around the He cluster. Loop punching occurred along the 〈110〉 crystal direction, which promoted further growth. The He-to-vacancy ratio was calculated as ranging between 1.5 and 2. When He atoms were randomly introduced into a Cu box, multiple He clusters were formed. Thermal diffusion promoted the formation of large He clusters. With the generation of more He clusters, more dislocations were formed, most of which were in the form of Shockley dislocations.